[lobster_johnson]

I believe I reported this once, but it's still there: You're hijacking alt-cmd-left/right, which I use for switching tabs in Safari. Your arrow-key event handler needs to have a guard:

    !(event.ctrlKey || event.shiftKey ||
      event.altKey || event.metaKey)

(Thanks for writing great documentation, though.)

[steveklabnik]

Yeah I'm not sure mdbook has patched it yet. I'll make sure a ticket is filed tomorrow, I thought we did, but am not sure. Even if we did, well, that's open source.